That’s all nice and good, but he completely missed the point that you have to dissolve the chalk in order to fully realize this alkalinity increase when observed as a pH increase in the mash.

There is a reason why I still stick with the old formula when the chalk has been dissolved even though this incorrectness was known for a while. Unless someone explains that, I don’t think we can change the spreadsheets w/o requiring that the chalk needs to be dissolved with CO2.

This is not a water engineering problem. This is a brewing science problem. If you titrate water with suspended chalk and the same water after dissolving the chalk you’ll get the same alkalinity. Everything makes sense here. I have done that since this was my first thought. But if you add malt to this water to make a mash you get different pH values. This is what’s not making much sense.

Well yes, chalk will not dissolve very much in water, which is why I advocate only adding it to the mash, where the lower pH of 5-6 allows it to dissolve readily. Dissolving CO2 into the water beforehand to dissolve the chalk will work, but it seems like too much work to me.

Kai, I am at work and don't have your paper available, but are you saying that the pH change when chalk is added to the mash do not match the predicted values? I guess I would not expect them to be perfect but I would expect them to be ballpark.

I found that using undissolved chalk, in either mash or water, only contributes half the alkalinity that you would expect from it and that there is also a saturation at which adding more chalk doesn't raise the pH anymore. I have run experiments where I added the chalk to water (those were part of the published paper) and where I added chalk to the mash (this data has not been published yet). In both cases the pH increase was not as much as I got from baking soda or dissolved chalk.

Since I found that the effective alkalinity of chalk in the mash seems to be only 1/2 of what you would expect I considered the spreadsheet correct and did not see a need to change it. In fact my own spreadsheet does the same. However, I added the option for using dissolved chalk and this is when 1g in 10l really adds 100 ppm as CaCO3 to the alkalinity.

I concur that the mash pH is low enough to dissolve any undissolved chalk brought in by the brewing water or added after dough-in. However, I have run enough experiments on this to say that this is not a calculation or procedural error on my side. This effect is real and some brewers have also reported cases where they kept adding chalk and nothing happened to the pH.

John is a pretty studious guy and from what I can gather of Colin, he is a pretty thorough and experimenting brewer. Unfortunately, I've met far too many professional brewers that have little to no knowledge of water and its effect on brewing and their beers showed it.

I'm hoping that John and Colin are having their book peer-reviewed prior to publishing since it would be a shame to have either of their reputations sullied and the reputation of Brewers Publication sullied by putting out poor work. This is a tough subject since it crosses many fields. Water chemists don't typically know anything about brewing and I find that few brewers know much about chemistry. Then add to that the need for water treatment to bring it all together.

Homebrewing and Craftbrewing are unique in their need to frequently assess and adjust their brewing water to better suit their upcoming beer. This differs from the needs of production breweries that brew thousands of barrels of the same beer per year. Consistency is the key for production brewers and they have little need to evaluate or change their brewing water. Through trial and error and advanced laboratory analyses, production breweries typically know exactly what adjustments they need for their brewing water. Homebrewers and Craftbrewers rarely have the tools or knowledge at their disposal to perfect their water and since they often change the beer they brew, they are the ones that need it.

There is no doubt that this is a tough subject. Most brewing text books provide a small chapter at best and most of them are still poor. John and Colin have their work cut out for themselves.

I'm hoping that John and Colin are having their book peer-reviewed prior to publishing since it would be a shame to have either of their reputations sullied and the reputation of Brewers Publication sullied by putting out poor work.

Martin, you should volunteer to read it for them. Randy Mosher asked me to read Tasting Beer before it went to the publisher, I like to think I was helpful. Having more eyes on it should only improve the final product.